Composition for fireproofing wood.



UNITED STATES PATENT LEOPOLD LITYNSKI, AUGUST RODAKIEWIOZ, AND FELIKSKUROWSKI, OF- LEMBERG, AUSTRIA-HUNGARY.

GOMPOSlTlON FOR FIREPROOFING WOOD.

SPECIFICATION forming part of Letters Patent No. 650,689, dated May 29,1900.

Application filed December 1, 1898. Serial No. 698,014. (No specimens.)I

To all whom it may concern:

Be it known that we, LEOPOLD LITYNSKI, AUGUST RODAKIEWICZ, and FELIKSKURoW- SKI, citizens of the Empire of Austria-Hungary, residing atLemberg, in the Empire of Austria-Hungary, have invented certain new anduseful Improvements in Impregnating Compounds for Fireproofing VegetableMatter; and we do hereby declare the following to be a full, clear, andexact description of the invention.

This invention relates to an impregnating compound for fireproofingWood, textile fabrics, paper-pulp, straw, and similar inflammablevegetable matter, the object being to provide a cheap and efficientcompound of this character.

This compound consists, essentially, of a solution of potassiumcarbonate and boracic acid in combination with a solution of basicmagnesium carbonate and boracic acid obtained by the addition ofammoniacal salts.

The use of potassium carbonate as a fireproofing ingredientis Wellknown; but the use in combination of boracio acid and potas siumcarbonate, whereby potassium borate is formed to'some extent, is notknown and hasa far better efiect. In consequence thereof the percentageof potassium carbonate, which must be very high when employed alone andhas an injurious effect on fabrics, can be con siderabl y reducedwithout impairing the fireproof properties of the fabric thus treated.An addition of from one to three percent. of boracic acid to from eightto twelve per cent. of potassium carbonate may suflice by way ofexample. This mixture has, moreover, the advantage of having preservingand antisep tic properties not possessed by the potassium carbonatealone and which are of great importance for the treatmentof wood. Inorder to still further reduce the percentage of potassium carbonate andof boracic acid, and thus render the process still less expensive,

the addition of magnesium carbonate con taining some boracic acid issubsequently made, this mixture or compound having strong fireproofingproperties and not having been previously discovered. The process iscarried on by adding to a solution of magne- 5o sium sulphate acorresponding volume of a solution of potassium carbonate or of sodaWhile subsequently adding a quantity of an ammoniacal salt, preferablyammonium sulphate, sufficient to dissolve the precipitate of basicmagnesium carbonate formed. A small quantity only is needed for thispurpose. The addition of the ammoniacal salt, the fireproofingproperties of which are well known,

is not used on account of such properties, as the small quantity usedwould scarcely have any appreciable effect. Moreover, such propertiesare inferior to those of potassium car bonate and boracic acid and tothose of magnesium carbonate and boracic acid; but this addition isresorted to in order to render the magnesium carbonate soluble by theaid of a chemically-inert factor. Then from one to two per cent. ofboracic acid is dissolved in the liquid, and this solution is mixed insuit able proportions with that of the potassium carbonate and boracicacid. A very satisfac tory impregnating fluid consists of twocompositions, the first of which consists of five hundred grams ofWater, one hundred and thirty to one hundred and forty grams ofpotassium carbonate, and ten grams of boracic acid well mixed and addedto a second composition consisting of five hundred grams of water, fortygrams of magnesium sulphate, 8o (MgSO twenty-five grams of potassiumcarbonate, (11,00 twenty grams of ammonium sulphate, (NIL) 80,, and tengrams of boracic acid.

It is obvious that the percentage of the various component ingredientsmust vary according to the nature of the material treated, the latterbeing soaked in the finally prepared solution and subsequently dried.For woody material it is necessary to remove the sap previously in amanner well known to experts.

We claim as our invention- A composition of matter for impregnatinginflammable materials to render same fireproof, consisting of a solutionof water, potassium carbonate and boracic acid, in the proportionssubstantially as specified, mixed with a solution of water, magnesiumsul phate, potassium carbonate, ammonium sulphate, and boracic acid, allin substantially the proportions hereinbefore set forth.

